4.4.            325

       .  -
       ,  
,     .

 Spanning Tree       .

       (root switch),  
 .       
 .     
    -   .

 ,   ,      
(root port)   ,        -
  (,      ).

  ,          -
   (designated port)   ,   
      .  
        -
,        .   ,
           
    (      -
   ).

        .
      ,  -
    ,   , 
     .

 . 4.38      
 ,   5   5 .   
 ,    ,    -
.     2  4   , -
  ,     .

         
          -
.   ,      (   )
  ,       -
   ,  .    -
  ,       
10        
. ,   Ethernet    10  ,  
 Token Ring 16 /  6,25. ( STA    -
   ,     -
,    .)

   ,      
,      ,  
   .

      
        -
  ,     -
  BPDU(Bridge Protocol Data Unit),     
 STA  .